causative verbs (-aせる/-させる)

I made my son cook dinner.
a. むすこに ゆうしょくを つくった。
b. むすこに ゆうしょくを つくってもらった。
c. むすこに ゆうしょくを つくらせた。
d. むすこに ゆうしょくを つくられた。

The answer is c.
[person]に [verb (-aせる/-させる)] is “to make [person] do …” or “to let [person] do …” This pattern usually implies that the person who you have do something is inferior to you because when the person is equal or superior to you, you would be using “～てもらう” or “～ていただく” instead.

How to change to causative is shown in the table below. With go-dan verbs, people often use shortened form which ends in -aす in conversation, but there are many people who think they are wrong, especially when the ending becomes -さす, so probably it’s better to avoid using them yourself at least for the time being. Make sure the verbs which conjugate in the vowel column, such as かう, いう and うたう, ”-a” part becomes わ.

	English	-ます	dictionary	causative
irregular	to do	します	する	させる
	to come	きます	くる	こさせる
ichi-dan	general rule	-ます	-る	-させる
	to watch	みます	みる	みさせる
	to eat	たべます	たべる	たべさせる
go-dan	general rule	-iます	-u	-aせる -aす
	to write	かきます	かく	かかせる (かかす)
	to run	はしります	はしる	はしらせる (はしらす)
	to buy	かいます	かう	かわせる (かわす)

The translation of other choices are:
a. I made dinner for my son.
b. I had my son make dinner for me (he did it willingly and I appreciate it.)
d. (I didn’t want him to do so) but dinner was made by my son (passive) (and I am not happy about it).

Some more examples of causative form:

I made my son do his homework.
むすこに しゅくだいを させた。(するirregular)

I made my son come to the party.
むすこに/を パーティーに こさせた。(くるirregular)

I made my son go to school.
むすこを がっこうに いかせた。(いくirregular)

I made my son read the book.
むすこに ほんを よませた。(よむ go-dan)

I let my son take a day off school.
むすこに がっこうを やすませた。(やすむ go-dan)

I made my son eat Brussel-sprouts.
むすこに めキャベツを たべさせた。(たべる ichi-dan)

I made my son get up at 4am.
むすこに あさよじに おきさせた。 (おきる ichi-dan)

The difference among “causative”, “passive” and “てもらう”

Can you explain the difference among the following 4 sentences?

a. エマはサラダを食べた。(straight forward)
b. エマにサラダを食べさせた。(causative)
c. エマにサラダを食べられた。(passive)
d. エマにサラダを食べてもらった。(てもらう)

The fact described by all these 4 sentences are exactly the same, “Emma ate some/the salad” but the circumstances are all quite different.

a. エマはサラダを食べた is just a straight forward sentence saying “Emma ate some salad.”
b. エマにサラダを食べさせた (causative) suggests that Emma didn’t want to eat it but “I” made her eat it, or that, if Emma is not able to eat by herself, I fed her with some salad.
c. エマにサラダを食べられた (passive) suggests that “I” wanted to eat the salad but before I had the chance to do so, Emma ate it.
d. エマにサラダを食べてもらった (てもらう) suggests that “I” didn’t want to eat the salad, so I asked Emma to eat it, expressly or not, and she obliged.